Herbert r



Sept. 24, 1929. H. R. BRUNNER FUEL COMBUSTION Filed. Oct. 7. 1925lTerberg j lirzaw r. WM

Patented Sept. 24, 1929 HERBERT R. BRUNNER, OF NEW YORK, N. Y.

FUEL COMBUSTION Application filed October 7, 1925.

My invention relates to fuel combustion; the object is to provideimproved method and means for insuring a uniform and suliicient passageof air into the fuel bed to generate con'ibustible out of the fuel bed,and also for carrying 011' the products of combustion from thecombustion chamber without carrying off the unburnt gases, in suchmanner as to insure efficient burning within the combustion chamber, soas to utilize, to the fullest possible extent, the heat units resultingtherefrom.

The invention is especially applicable for burning such fuels asbuckwheat coal in domestic heating plants and comprises improved methodand means for supplying air to the space beneath the fuel bed (the ashpit) of such ample volume and of such pressure only as to assure theeven distribution and passage of the air into the fuel bed withoutappreciable assistance from the draft in the stack or chimney, and in soregulating the stack or chimney draft, and the supplemental airdelivered to the combustion chamber, that all the delivered above thefuel bed, will be consumed in the combustion chamber and only the burntproducts will be carried therefrom. In this manner the heat generated bythe fuel combustion is utilized to the fullest possible extent.

The invention also comprises improvements in details of construction.

Referring to the drawings, which illustrate merely by way of examplesuitable means for effecting the invention Fig. 1 is a part verticalsection.

Fig. 1 is a fragmentary view showing air inlet damper.

Fig. 2 is a top plan view.

Fig. 3 is a part plan View showing the ash door open.

Fig. l is a horizontal section of part of the device as shown in Figs. 1and 2.

Similar numerals refer to similar parts throughout the several views.

Serial No. 61,015.

In the arrangement shown in the drawings, the furnace 7 is of usual typehaving the door 8 opening to the ash pit 9. This door 8 is ordinarilyprovided with a draft opening 10, normally closed by a gravity actuateddamper, the plane of the margins of the opening being inclined to theperpendicular. This damper being removed, an adapter 11 is secured tothe door 8 and surrounds the margins of opening 10. The engaging marginsof the adapter are, in the example, shown, in a corresponding inclinedplane, while the main body of the adapter 11 has an approximatelyhorizontal extension. To the opposite side of the adapter, from the sidesecured to the door 8, is secured the chambered body 12, which is shownsubstantially of rectangular formation. The front end of this body 12,is provided with the damper or door 13 and the adjusting are and handleformation 14.

It will thus be seen that the adapter 11 and chambered body or box 12form a selfcontaining unit secured to and entirely supported by the ashdoor of the furnace, and

adapted to swing with the door when the same is opened and closed. Theopening 10 is of ample dimensions, usually as large as the door 8 willconveniently permit. The throat of the adapter 11 is sli htly largerthan the opening 10. The throat or vertical crosssection of the chamberof body 12 is also slightly larger than opening 10. Vithin the chamberof body 12 is provided a ring or short cylinder 15, within which issuitably positioned a fan 16 supported and driven by the motor 17,secured and supported in any suitable way within the chamber of body 12,as by the spider 18. Between the chambered body 12 and the adapter 11are provided the slidable shutters 19 for the adjustable control ofcommunication between the ash pit 9 and the chamber of body 12. It willbe noted that the adapter 11 and chambered body 12 are so proportionedand positioned as not to interfere with ready access to the ope 'atingends of the grates which are normally on closed. by a. drop door asshown.

Above the fuel bed 20 is the combustion chamber 21. provided with theusual controlled air inlet Ql, and the usual smoke pipe 22 connectingthe combustion chamber to the static or chimney flue, not shown. Thissmoke pipe is provided with a suitable damper as at In operation, havinga fuel bed of normal dimensions, composed of buclcwhaat coal or similarfuel, a volume and pressure of air provided beneath the fuel bed toassure an. evenly distributed passage 0" the air into said fuel. bed,and a delivery 0 gas therefrom into the combustion chamber above thefuel bed.

This volume and pressure is approximately adjusted, or relative to themass and density of said fuel. bed, in order that the proper amount ofgas shall be generated from the fuel, for burning in the combustionchamber. This pressure depends very slightly, if at all, upon the draftof the stack or chimney flue, since, in such case, tl c draft. wouldtend to carry off from the combustion chamber a large amount of unburnedgas, or prodnets of combustion from which the heat units had. not beenextracted, thus causing serious waste of heat units.

By creating a large volume of air, at a relatively low pressure, in theash pit or space below the fuel bed, and utilizing a relatively lowpressure above the fuel bed, due to the stack flue, there is securedsuch a passage of air into the fuel bed as will. result in a combustiblegas delivered to the combustion chamber, above said fuel bed. This ismixed with sufficient air, from the controlled inlet 13, or otherwise,for insuring combustion, so that the gases will be entirely burnedwithin the chamber. The stack draft is so reduced that the products ofcombustion will be retarded, or will idle through the heatin spaces ofthe furnace and thus permit, to the fullest extent, heat transferencefrom the products of combustion to the medium of heat circulation, suchas air, water or steam,

the case may be, and only the burnt products with most of the heatextracted therefrom, are carried away by the stack flue.

Merely by way of example, assume that '10/100 of an inch pressure wererequired to -ause the desired and evenly distributed passage of air tothe coal bed, an ample volume of air is provided beneath the fuel bed,at a pressure of about 8/100 of an inch, permitting only about 2/100 ofan inch pressure to be created by the flue draft, in order to secure thecomlitions as above set forth. \Vhereas, if the entire pressure of10/100 of an inch, necessary to cause the required flow of air throughthe fuel bed. were to be aused by the flue draft, it will be seen thatthe suction in the combustion chamber above the fuel bed, would resultin carrying away the combustible gases, or even the burnt products sorapidly as to result in great heat losses, and this condition, inpractically all domestic heating plants burning such coal as buclcwheat,has been found actually to exist.

My invention therefore consists essentially in. providing a. volume andcreating a pie.- sure of air beneath the fuel bed, the pressure nearlyor quite sutlicient, never under any conditions excessive, to cause theevenly distributed passage of air into the fuel bed, and perniitt'in thestack or chimney flue to exert a. suction on the combustion chamberbarely sufficient to carry therefrom the products of combustion afterhaving delivered. to the 011'- culating medium, the major portion oftheir heat units.

As a convenient means for carrying out the invention, it should be notedthat the pan is preferably designed, especially with respect to pitch orangle of; blade, as to produce an approximately definite staticpressure, under varying conditions, as for example, air spaces ofvarying dimensions.

It will. also be noted that the booster unit comprising the fan, itshousing and associated elements, delivers to the regular and usualchannel of the ash pit draft. It in no way changes or alters thisimportant function of draft, except to accelerate or boost the d 'aft orair flow into the fuel bed from underneath, as and when required. Ineffect it is a means of turning up the gas; increasing the gas flow fromthe fuel bed. (the gas producer) at will, as required.

It will also be noted that my device is adapted normally to permit theuninterrupted course of draft .in the accustomed manner in a wide rangeof heating units; that is, the regular and accustmned ash pit draftmanagement is not disorganized, but when desired, all the elements ofthe ash. pit draft may function normally.

What I claim is 1. In. combination with a heating furnace, having ahinged ashpit door with a draft opening having margins in a planeinclined to the perpendicular, a fan and motor and a housing therefor,an adapter comprising a chambered formation open to the draft openingand to the fan and motor housing, said adapter having cooperatingmargins in a plane corresponding to that of the margins of the draftopening, secured to and supported by the ashpit door and secured to andsupporting the said housing, and horizontally slidable shutterspositioned between the adapter and the fan and motor housing.

2. In combination with a heating furnace, having a hinged ashpit doorwith a draft opening having margins in a plane inclined to theperpendicular, a fan and motor and a housing therefor, an adaptercomprising a lll) chambered formation open to the draft opening and tothe fan and motor housing, said adapter having cooperating margins in aplane corresponding to that of the margins of the draft opening, securedto and supported by the ashpit door and secured to and supporting thesaid housing, the adjacent Walls of the adapter and of the fan and motorhousing cooperating to form horizontal Ways for shutters and shuttersslidable therein.

HERBERT R. BRUNNER.

